"austerity" was a word used by lefty marketing types, as it sounds so negative. In reality it's just only spending what you actually have, i.e. being responsible. Sadly the BBC lapped up this crap at the time, implying it was all bad and was just a brief period, after which the reckless entitled borrow-to-spend New Labour policies would be back in force, which is what happened, ironically under the tories after they sold out.
It's a lot like "progressive", which is a lovely positive sounding word that has been adopted by the BBC and chums to describe socialism. It sounds great, who doesn't want to progress? In reality it means handing over your money, under threats of state violence, so that they can waste it all on crap you don't want.